Field-magnet.



UNITED sTATEs PATENT oEEioE. 4-

WILLIAM D. IOMEROY, OF NORWOOD, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TOTHE BULLOCK ELECTRIC COMPANY, A CORPORATION OF OHIO.

FIELD-MAGNET.

Specification of Letters Patent.

Patented Dec. 31, 1907.

I Application filed October 30` 1903. Serial No. 179,191.

vTo all 'whom it may concern:

Be it known that I, WILLIAM D. POMEROY,` a citizen of the United States,residing at Norwood, inthe countyv of Hamilton and State of Ohio, haveinvented certainlneW and useful Improvements in Field-Magnets, of whichthe following is a full, clear,- and exact specification.

M invention relates to dynamo-electric mac ines, yand particularl tomachines of the revolvin field type. n these machines it isfessentia notonly that .all parts should be firmly heldin place, when firstassembled,

' but it is necessary to provide a construction which vwill prevent anypossibility .of the parts working loose.

By my invention the coils are securely held from displacement by beingclamped a ainst a coil seat which is compressible.

is compressible seat is separately removable and renewable and adaptedto be easily .adjusted to a suitable size. In addition to part of afield pole in section; Fig. 2 is a section on the line of Fig. l; Fig. 8is a bottom plan view of the coilseat casting; Fig. 4 is a sectionalview on the line 4-4 of Fig. 3, and 5 is -a perspective "view, onl areduced scale'showing a modified form of seat for 'the coil.

An arm of the revolving field structure is indicated at l and the rimthereof at 2. The

pole pieces are secured to the vrim at equal .distances apart andonly'one is shown, as the structure of each is the same. The pole may besolid or laminatedand secured to the rim" 2in any of the usuallways,such as by bolt, dove-tails, etc. In the present instance I illustrate apole made up of laminations 3 clamped together between end plates 4 bthe rods 5. The pole piece thus built up is c ovetailed to the rim asindicate( in dotted lines at 6 and tightened in place by the keys 7. Thelaminations and end plates 4 are formed with the projectingV portions ortips 8 and each end plate is provided with the flange 9.

A continuous rim is thus formed entirely around the pole piece andeffectively prevents outward displacement of the coil 10. This is shownas consisting of a conductor of large cross section wound edge-Wise, butmay consist of round wire or a combination of the two. The coil isprotected on the inside by the insulating cover Il and on the ends bythe fiber-collars 12. The coil fits loosely over the core of the pole.

The base of the pole is encircled by the metal casting 13. This consistsof a light frame which may be of cast iron and is L shape in section. Itis provided with pockets 14 on .oppositesdes These may be of an size ornumber as is found most desirab e. fBlocks of wood 15, or othercompressiblel material, are placed in pockets '14 and contact with therim 2. the casting 13 is curved to conform to the peripher of the rimbut is spaced therefrom by the b ocks 15. On each of the inner sides ofthe frame 18 are formed one or more projections 13 which may be fileddown to form a tight fit around the core of the pole piece. Whenmachines are so large that the curvature of the periphery is slight, Imay do away with the seat as above described and use a continuous ri ofwood or other compressible materiiil, such as is illustrated in Fig. 5.v

Two opposite sides of the coiland seat extend beyond the'sides of therim and are supported on each side by end rings' 16. These are built upin ribbed form and the radial ribs 17 and the outer and inner rims 18and19 not only make the rin s strong struc turally, .buth also form poc ets20. These pockets are used for the urposel of balancing the machine andmay e filled or artially filled with lead for this purpose.. W en it isdesired to weight one side, a smallhole is bored in the pocket on thelight side and the necessary amount of melted lead vpoured in when thepocket is at'its lower position.' The lead then solidifiesinthat part ofthe pocket which is most distant from the axis of the 'shaft' andtheinclined sides will prevent displacement of the lead. Certain of theribs are enlarged as at 21 to receive the-bolts 22, which secure 4thering to the field frame. The periphery of the ring is inclined ortapered as at 23, and the innerlportion of the ring engages the face aswell as the interior f surface of 'the rim 2 as shown at 24.

In assembling the parts, the coil and seat The bottom face of with theWooden blocks are placed over the core of the pole piece, which is thensebination o cured by bolts, keys, or otherwise, to the frame. Theblocks are madeof such depth that in securing the pole to the frame, theparts are com ressed,and' this compression causes the coil to be heldrmly in place. When the blocks are made of wood, a compression of 11,16is found to be sulicient. Afterthe poles are secured in position, the

end rin s are bolted in place andthe struc- 'j ture ba anced as aboveexplained. V The tapered portion ofthe rings permits them to be readilyplaced Within the ends of the coils and seats, and when secured inposition form an additional support for those parts. f

I claim asv my invention:

1. In a d namo electric machine, the combination o a frame, a pole.piece secured thereto, a coil on the pole piece, and'a separatelyremovable compressible seat vat one end of the coil 'and encircling thepole piece.

2. In a d namo electric machine, thecombination ofy a frame, a polepiece secured thereto, a coil on the pole piece, and a'separatelyremovable compressible seat betweenthe coil and said frame.

3. In a d namo electric machine, the coml bination ofY a frame, a polepiece secured thereto, a coil on the pole piece, and means encirclingthe pole piece at one end offthe .coil and comprising, se aratelyl`removable yieldable material, su stantially" as de-j scribed.

4. In a dfynamo electric machine, thecom- `a frame, apole piece-"securedthereto, a coil on the pole piece, and acorn# pressible seat between thecoil and.' said' frame, said seatrcomprising a frame and' compressiblematerial. p i 5. In a dynamo-electric machine, the coma frame, av pelepiece secured thereto, said ole'piece having.projecting portions, a co'on the pole piece, and a com- -pressible seat between the coilmand said4inner ends of 9. I na dynamo-electric machine,the combinatio'n of aframe, ,pole pieces, having proframe said seat comprising a frame havipockets and compressible material in sali pockets.

6. In a d'namo-electric machine, the c'omy bination o piece securedthereto, said ole piece having projecting portions, a coilp on the polepiece, and a comprressible seat between. the coil and said ame, saidseat comprising a metal frame Which encircles the pole piece, and comaframe, a pole prressible [material in pockets in said metal ame.

7. In a dl llamo-electric machine, the combination o a frame, pole'pieces secured thereto, said pole pi'eces having projecting portions, alco1 oneach of sai ole pieces and an.end` ring having anlinclineci)periphery which engages the inner ends of the coils.

8. In a d namo-electric machine, the combination o a frame, pole piecessecured thereto, said le pieces having projecting 1portions,.a co oneach of said pole pieces and an end ring having'v pockets, the peripheryof said rinlengaging and supporting the S ecol jectlnportions secured tosaid frame, a coil on eac pole piece, a seat of compressiblematerial'between each coil and the frame,and an endrng having pockets,theperiphery'of said ringen'gaging'and assisting tosupport the c oi'ls.`l

' 10. In a dynamo electric machine, the combination'of 'a frame, a polepiece secured thereto, a coil'on the Eole piece, and se a ratelyremovable yields le means located e- Atw'een the coil and said iframe,substantially as described.

.In testlmony whereof I affix mv signature,

in presence of two witn.

; WILLIAM D. POMEROY. Vllitm'asses: .A v SANFORD KLEIN1 L K. SAGER.'

